a b s t r a c t Omnivorous fish util

a b s t r a c t

Omnivorous fish utilize dietary carbohydrates better than carnivorous ones due to striking morphological and physiological differences in their digestive tracts. However, digestive tract morphology and physiology also varies among omnivorous fishes, which can lead to different dietary utilization of plant sources as well. Starch, energy, and dry matter apparent digestibility coefficient (ADC) of wheat bran, cassava residue, ground corn, and broken rice were compared between the omnivorous freshwater jundiá catfish (93.9 ± 34.0 g; mean ± standard
−1

Keywords:

deviation) and Nile tilapia (93.7 ± 51.6 g) by using 5 g kg

chromic oxide as a diet marker. Starch ADCs were

Carbohydrate
Starch digestion
Scanning electron microscopy
Starch spherulite

significantly higher in tilapia for all plant sources (92.02% to 99.74% versus 55.87% to 90.61%), except for wheat bran, which was similar to that found in jundiá. Starch-richer plant sources (ground corn and broken rice) showed the lowest starch digestibility for jundiá. However, ground corn provided significantly higher energy digestibility in jundiá (55.35%), as opposed to broken rice (86.59%) and ground corn (71.68%), in tilapia. Dry matter ADCs ranged from 22.89% for cassava residue in jundiá to 89.17% for broken rice in tilapia. Higher dry matter ADCs were registered in tilapia for all plant sources, except for wheat bran. Despite presenting lower starch and energy digestibilities, jundiá catfish showed an adaptive capacity to utilize starch sources by present- ing significantly higher specific activity of amylase (58 U mg protein−1 versus 29 U mg protein−1) and maltase than Nile tilapia for all plant sources, except for wheat bran. Maltase activities in the gut of jundiá varied from 2.5 to 3.6 U mg protein−1, depending on the plant source, while in tilapia it averaged 1.7 U mg protein−1, regardless of the plant source. The scanning electron microscopy approach used to study the influence of fish digestion on the structure of starch granules from different plant sources revealed the presence of spherulites in the fish feces. Starch spherulite formation in jundiá intestines could be related to lower starch digestibility. Our findings demonstrate different carbohydrate digestion abilities among omnivores.
© 2014 Elsevier B.V. All rights reserved.

ผลลัพธ์ (แอฟริกา) 1:

abstrakte Omnivoor fi SH Gebruik dieet Koolhidrate Beter as vleisetende Ones Weens treffende morfologiese en fisiologiese verskille in hul spysverteringstelsel stukke. Maar, spysverteringskanaal morfologie en fisiologie wissel ook onder omnivore fi shes, wat kan lei tot verskillende dieet benutting van die plant bronne as well. Stysel, Energie, en Droëmateriaal oënskynlike Verteerbaarheid Coëf fi kend (ADC) van koring semels, Cassava oorblyfsel, Grond koring en Broken Rice is vergelyk tussen die Omnivoor varswater Jundiá Kat fi SH (93.9 ± 34.0 G; gemiddelde ± standaard -1 Sleutelwoorde: afwyking) en. Nyl tilapia (93,7 ± 51,6 g) deur gebruik te maak van 5 kg G chroom-oksied Dieet as 'n merker. Stysel ADCs was Koolhidraat styselvertering skandeerelektronmikroskopie Stysel Spherulite beduidend hoër plant bronne in tilapia vir almal (92,02% tot 99,74% 55,87% tot 90,61% teenoor), behalwe vir koring semels, wat soortgelyk aan dié wat in Jundiá was. Stysel-ryker plant bronne (grond koring en gebreekte rys) het die laagste stysel verteerbaarheid vir jundiá. Maar grond koring voorsien beduidend hoër energie verteerbaarheid in jundiá (55,35%), teenoor rys (86,59%) en grond koring (71,68%) te verbreek, in tilapia. Droëmateriaal ADCs gewissel van 22,89% vir maniok oorskot in jundiá te 89,17% vir gebroke rys in tilapia. Hoër droëmateriaal ADCs geregistreer in tilapia vir alle plant bronne, behalwe vir koring semels. Ten spyte van die aanbieding van 'n laer stysel en energie digestibilities, jundiá kat vis het 'n aanpasbare kapasiteit stysel bronne te benut deur teenwoordig ing beduidend hoër spesi fi eke aktiwiteit van amilase (58 U mg proteïen-1 versus 29 U mg proteïen-1) en maltase as Nyl tilapia vir almal. plant bronne, behalwe vir koring semels. Maltase aktiwiteite in die ingewande van jundiá gewissel 2,5-3,6 U mg proteïen-1, afhangende van die plant bron, terwyl dit in tilapia dit gemiddeld 1.7 U mg proteïen-1, ongeag van die plant bron. Die skandering elektronmikroskopie benadering gebruik om die invloed van vis vertering van die struktuur van styselkorrels van verskillende plant bronne te bestudeer het die teenwoordigheid van spherulites in die vis ontlasting. Stysel spherulite vorming in jundiá ingewande kan verband hou stysel verteerbaarheid te verlaag. Ons bevindinge toon verskillende koolhidraatvertering Vermoëns Onder omnivore. © 2014 Elsevier BV Alle regte voorbehou.